Apparatus for making annular tubes.



S. C. HATFIELD.

APPARATUS FOR MA ANNULAR TUBES. APPLICATION FILED MAR. 31, 9 RENEWED MAY 13.1916- 1,208.777.' Patented 19,1916.

25H MEET l- S. C. HATFIELDY APPARATUS FOR MAKING ANNULAH TUBES. APPLICATION mm MAR. 31.1913. RENEWED MAY 13,19l6.

1,208,777. Patented Dec. 19,1916.

2 SHEETS-SHEET 2- cfmc HATFIELD, 0 BALTIMORE, MARYLAliTI-l.

flIEEEflJ-KA'EUS HUB MAKEHG ANNULAR TUBES.

Fapecificatiou of Letters Patent.

Patented Dec. 19, 191.6.

Agipiicaficu 111cc liiiaych M, 15913, Serial No. 757,834. Renewed May 13, 1916. Serial No. 9?,482;

To (ZZZ whom it may ccncem:

Be it known "JllEl'lJ ll, SCHUYZLER C. HA1 FIELD, citizen cf the United States of 'Aiiieiice iresicliiig the ciiy cl lir ilbiiiioize State of Maryland, have invenied certain new and useful improvements in Apparatus fer Making Annular Tubes, of "which the following is s specification.

This invention relates to ii new apparatus for making single tube pneumatic tires.

Single tube tires of the nature describecl can be made by coating permanent fcrm, then slitting the rubber, i'eincving the tube from the form and vulcanizihg to close the break made for the purpose of freeing the hire from the form. Such rubber tires with their treads reinforced by means of fabric were found quite satisfactory for use on bicycles, but they are not of euiiicient strength to resist the pneumatic pressures which are necessary suppci'tthe heavy motor vehicles of the present (lay. For this purpose 2i tiic Whose Walls are i'eiiifcrcecl throughout by heavy fabric is used, but such tires under the presen practice are heceseerily of the double tube variety, the outer tube or shoe being open along its entire inner periphery, the opening being closed by i-he rim. This opening provides easy means for removing the tire fabric from lei-in, but withthc single cube tire m such. opening exists, and if a time made oi fabric and rubber is cut to remove in from the form, the opening cannot be closed $0 Mlvaiiiage' so as to give the tire the necessary sii'ength at to so clese it is exceeclingly expens e.

The object of the present invention to provide :1 form or internal meld fey use inmanui'actui'ing a single tube iii-e ccmpcsecl of rubber and fabric the leinier being" embedded in the rubber and Wcund. about the circumference of the tube sc that the Wells of the tire throughout, and at all paints ewe strengthened and suppciriecl by the fabric, and the tire thus formed may be sufficienc strength 1330 support the heeviesi: motor vehicles new in use.

As c result of my iiiveiiticn' 1 provide e temporary internal mclcl or 013? of cocm pzii'utively fragile material, which, While capable of supporting the febi'ic c1141 ing the tension thereof alumn settling of tie materials, may be easily brc' eu up and red cc l to p wdered c3 gicnuiei icrm an through the valve opening,

The mold used in its preferred form is built up of two annular rings of substam tiully semi-circular cross-section, the fiat lacebeing in the plane of the ring. The rings 01' annular iiiembei's thus described are, in the practice of the mcthod prefcn ably formed on a lint incli'ling bcercl or sup part upon whicl'i a swinging arm is pivoifially mountezfh and the arm is apex-cured or notched in the form of the crossscction cf the minulzir' members of the racial a, point spaced from the center or pivot by e disfiance equal in the radius form the annular members iei'ci'ceii t0, lihe molding material which is preferably pies ice of PflT'iS, is applied. lo the bozmi and dis- 'l'l'ilHilIMl along the circumference swung by the notch when the aim. is rclziiiecl ebcu lite center. 'i'lhen su'llicient the metecial is ill place, the arm is given burn or two abcut its center anal bhe annulus fcimec. Have ever, it is found ilesirzible in civic? dshet ihe internal meld may be easily broken up \viihin We tire to have ilhe annular incite bers bellow This is easily ccccmplishccl by the use of (H1 annular coi'e which the molcling material is applied in c i'cugh cecal; ustced ef being ilistiibutei along" the board. After the core is thus coated, the rciteticzi of MIL swinging arm forms the annulus previcusly described When the molding maizerial has set, the annulii'i is removed and placed on a suitable suppo ei. with the annular opening upward. The receptacle thus fci'meci is filled with send or other finely clivideil material and the opening is preferably ccvareal with plaster of Paris or the equivalent e) prevent the escape of the send To farm the mold live annular members are placed face be let face. They/ere then Wcuncl Wiijll fehi'ic and coated ith rubber, and vulcanized as previously described.

The ecccmpanying drawings iilustrete en till lllll lllll ap niratns constructed according to my in -rention ,aud theoperation thereof.

A l, no 1 is a pcrspiurtire ()l the molding board sluin'ving the nmldinp; arm and an aunular core in the process of frn'nmtion. Fig. 2 a 'tion of the same. Fin. 3 a transverse on thrmjlgh-the end oi? the molding arm showing; the i'nold torl'ner in position. llig. 3 a similar \ltW showing the core ,Eljllll'l'lGlI'. Fig. lis a 'longritlulinal section. of the same portion of the molding arm showii'ip" the mold former in position. F 5 a View corresprmding to Fin". .2 showing the apparatus in the procb. of forming a hollow annular mold rii'igol scan-circular cross-section. Fig. ll is a transverse section through th finished mold. lfig. 7 is a similar "viewslunvmg a tire in the process of for mation, the rubber coating; being cut away to show the fabric.

The tPPlHfiltlIS, as illustrated, consists of a :l'lat mol 'ing board 1,. a swinging molding; arm 2 pwotally moimted on the board at S, the arm being cut away or notched at at to clear the mold or otherwise adapted to support a mold formir plate 7, the plate being apertnrod in the 'm of the mold to be :liorined anul scour id to the arm by means of.

bolts 6, so that the l orn'ling, plate overlies the aperture in the arm. llsmilly the mold is :tora'ned. in two sections divided on a plane at right angles to the axis of the tire, and therefore the aperture l oil. the mold former is substantially semi-circaular, and the notch in the mold and the opening in the "former are spaced from the pivot 23 by a. distance equal to the radius ol" the tires to be formed.

lln the imeration to be described, the annular internal. molds used are preferably till) within the mold.

made hollow, and the :iiperture within the mold 1:; formed by means (d an annular." core 7 9. The rotating, arm 2 may beused to ad the annular core which is ),rmation ol the hollow To animal; the suaparatus to the production oi. the core, the core forum]: 5 is used instead. of the mold former. The core trumor aplate a'pertured to conterm to the cross-section of the core and is secured to the arm 9, by means of bolts? wl'iich also used to hold the l]'1()l.(l f01l'l'l6l 1". Pro .erably the core has a. ribbed surface ya ntage in main ng necessary to the and the oliicningzj 1n the core formeris notched or scallopcrjl to give tl". is ell'ect. llfloth the formers are so constructed that they may be ap 'ilied to the arm and removed then-it. om and interclmngged at will.

The preferred form 01? the invel'ition is used as follows: ll the internal molds or harms upon which the tire is to be built up are to be hollow, the core ".lbirmnr 5 is a n'ilied to the arm. llll'lfi arm is pivotally inolmted on the board, and a qurrnti y of molding material in plastic form, 1 .1 ably plaster of H or the lilre, is applied to the board in tated-twining an annular core see Figs. 1 and 53. The core then coated with some suitable material as shellac 16 which will prevent the mold sections which are to be made over the core, from sticking tl'iereto. The core frn'mer 5 is removed at any convenient time. and the mold former secured to the arm. material is applied to the core 9 and the arm is rotatelfl, girii'ig the plastic material, indicated by reference character ll), an annular form, substantially semi-circular and similar in cross-scctimi to the cross section of the tire, divided centrally, as illustrated in Fig. 5. After the plastic material has set, the pivoted arm l having first been disconnected, the annular members 10 are removed and placed on a suitable support with the 12 in the annulus 10 is then filled with sand or other finely divided material, and the surface corresponding to the opening 11 is c0vcred with plaster of Paris or other plastic 13 and smoothed by means of a fiat instrument. Two of the annular members 10 are then placed with the fiat facesli in contact and wound with a strip of suitable fabric or fibrous material 14.- to be used in the construction of the tire, after which the mold with the fabric is covered with rubber and vulcanized. The tire may be made of A quantity of molding any suitable thickness, the layersof textile fabric and rubber alternating, and the layers of fabric are helically wound. about the mold and. the adjacent layers are oppositely wound or disposed, as illustrated, to resist stresses in all directions, The outside layer is usually ofrubber, and when the material is all in place on the mold, the tire is yulcanized. A suitable valve opening 15 is formed by burning the rubber and fabric 01 in any other convenient manner. The whole mold is then reduced to a powder or. otherwise broken by beating the tire; The finely divided material is shaken out through the valve opening 15, and the opening is closed by the insertion of the valve If it desired to use solid ring members instead of making: them hollow as described,

it is obvious thatthis can be done by omit-' ting, the core. In this way the process can be simulified but in this form it is considered less etl'cctive. y 1

Thus a seamless tire is formed of continuous fabric mated and limprcgaated with rubber, and by this method the fabric may be made as heavy and the tire as stronq as desired, {IlVlIlg a single. tube tire of suflicient strengtl'i to be used with the heaviest motor 'matie tires consistin mold material varies and the apparatus itself may be widely changed within the scope of the invention.

What I claim and desire to secure by Letters Patent is:

1. An internal mold or form' for pneuinatic tires consisting of, a hollow, annular plaster shell filled with finely divided material. v

2. A core or mold for pneumatic tires c0nveieting of a plaster of Paris shell in the form an annular tube filled with sand. 3. An internal mold or form for pneuof a frangible shell efilled with finely divided material.

4 An annular internal mold or form for pneumatic tires consisting of a frangible.

ered and the halves superimposed one upon another to form an annulus having a frangible shell with a finely divided filling.

Signed by me at Baltimore, Maryland, this 29tl day of March, 1913.

SCHUYLER C. HATFIELD. Witnesses:

ZELLA KUHN, EDWIN F. SAMUELS. 

